It was also a sign of the times that Unreal 2.0 debuted with America's Army, a licensee and not an internally produced title. In the same year, the artist Mary Flanagan also turned to Unreal 2.0 for "Domestic," which offered a haunted passage through the memory of a burning house, mixing poetry, cinema, and nostalgia into an interactive first person exploration. It's a testament to the emerging flexibility of Epic's toolset that two such dramatically different experiences, one a military recruiting device and the other an emotional reverie, could be created using the same technology.

America's Army on Unreal Engine 2.0

Unreal 2.0 also moved the business of engine licensing forward with an unprecedented volume of deal making at the highest level. Unreal 2 was used for Tom Clancy's Splinter Cell, Deus Ex: Invisible War, EA's Harry Potter games, Red Steel, BioShock, and Mirror's Edge (to name only a few big ticket games). It was also during this period that the very idea of a game "engine" began to stretch. In the mid-90's "engines" were often used to make clones, or DOOM-likes as the FPS was once called. With the advent of Unreal 2.0, saying something built on a particular engine didn't necessarily dictate the kind of experience you would have.

"An engine has nothing, or at least very little, to do with how a game looks visually," Sjoerd de Jong, long-time Unreal modder and developer of The Ball, told me. "You could produce an Unreal Engine game that looks like a 2D retro game, a realistic war game, or a brightly colored cartoon game for kids."

The additions to Unreal 2 were largely focused on integrating a wider variety and depth of the available tools. The engine had integrated tool to support Karma's physics system, the rendering system was rewritten for even more efficiency, a new particle system was added, and the Unreal Editor was updated for usability and performance.

"The Unreal Engine is not a static piece of software," Geremy Mustard, of the Epic-owned Chair Entertainment, said. "Epic is constantly adding new features, optimizations, and improvements."

While continuing to develop its own internal projects, Epic has worked hard to build a support network and make its engineers accessible for licensees working with their technology. Likewise, a huge body of shared community knowledge has made the engine approachable for the new-comer. "The Unreal community is over ten years old. It has a good mix of experienced people who have been around since the early days, and many new people," de Jong said.

"When we did get stuck there was the ever helpful Unreal Developers Network, and the dozens of tutorials written by the community."

But Have You Played it in HD? Having already made great headway in establishing engine-licensing as a major part of their business, Epic was even more ambitious with the release of Unreal Engine 3. While UE2 supported home consoles, it was released several years into their various life cycles, meaning the engine had to adapt to the out-dated hardware. With the third official iteration of the engine Epic had a chance to tailor the experience for the coming generation of HD consoles and harness their power from the outset. In 2005 Epic announced Gears of War as the graphical showpiece for what the Xbox 360 could do using their technology. Epic's Vice President Mark Rein later boasted that he and Sweeney were able to convince Microsoft to double the onboard RAM in the system (from 256MB to 512MB) after seeing the equivalent difference in graphics in a screenshot from Gears.

An early look at Unreal Engine 3

Sony was given a timed console exclusive with the PlayStation 3 version of Unreal Tournament 3 to fire a similar sense of graphical wonderment in its partisans. In the build-up to the launch window of each system, there was a steady string of announcements from Epic about new licensees for its nascent tech. Square-Enix, EA, Ubisoft, Disney, THQ, SEGA, Activision, Midway and more signed on for Unreal 3 licenses. Many of the most-anticipated titles in the early days of the 360 were powered by Unreal 3, including Gears of War, John Woo's Stranglehold, Medal of Honor: Airborne, Blacksite: Area 51, and Brothers in Arms: Hell's Highway. It seemed that Unreal Engine 3 might come to define development on high definition consoles.

But then rumors of development teams struggling with the new tools began to roll in. The big increase in technological capacity made stunning visuals possible, but it also made development significantly more expensive and complicated than it had been. As Epic continued to add updates to its engine in the run-up to launch, developers with milestones to complete often struggled to keep pace. In a post-mortem published in Game Developer magazine, team members from John Woo's Stranglehold lamented their time lost trying to make new versions of the engine work with content made using earlier versions. Then there were reports of the difficulty optimizing the PS3 versions of multi-platform games. After lack-luster receptions for The Last Remnant, Square-Enix president Yoichi Wada said the company's future use of the engine would be made on a "case-by-case basis."

The rumors all came to a head in mid-2007 when Silicon Knights, which had proudly announced their licensing of UE3 two years earlier, filed a lawsuit against Epic claiming UE3 never did what they had been contractually promised. They declared they would instead have to build their own engine for Too Human, causing major delays and millions of dollars in lost development resources.

In spite of the tumultuous start to the generation, the turbulent reports of struggle have abated. While the early years of this generation might have pointed to a near ubiquitous adoption of UE3, a healthy variety of different technologies have emerged. Meanwhile, Epic's technology has quietly continued in big performers like Army of Two: The Fortieth Day, Mass Effect 2, BioShock 2, and Splinter Cell Conviction. Some of those games are built on heavily modified versions of UE 2.5, but the core suite of tools that Epic built remains consistent.

"I think our tools have always been what makes Unreal Engine so powerful," Rein told me. "Recent improvements like UnrealKismet and Matinee have been a big factor in our ability to make games that are competitive on a world stage even with smaller teams than many of our competitors."